Flex accessing custom component's children properties

Question

Is there a way to access children's properties of a custom components from mxml and not from the actionscript.

For example, i have a component "A"

<s:Group>
   <mx:UIComponent id='childA'/>
   <mx:UIComponent id='childB'/>
</s:Group>

And somewhere in the application i want to do something like this

<s:HGroup>
   <components:A>
      /*I want to access properties of this children objects*/
      <childA width="20"/>
      <childB color="0xFFFFFF"/>
   </components:A>

   <components:A>
      /*And here too*/
      <childA width="60"/>
      <childB color="0x000000"/>
   </components:A>
</s:HGroup>

JeffryHouser JeffryHouser · Accepted Answer · 2013-06-20T10:22:20

You can do this in ActionScript; but not in MXML. In ActionScript:

componentAInstance.childA.width = 20;
componentAInstance.childB.setStyle('color',0xFFFFFF);

This is what we call a horrible break in encapsulation; becahse the "parent" should not need to know about the implementation details of its children.

ComponentA should know how to size and position its own children; in this chase childA and childB. It should not need help from ComponentA's parent.

You may find benefit in reading this blog post about how component's should communicate with each other.

Flex accessing custom component's children properties

1 Answers